Calculation and analysis of hyperfine and quadrupole interactions in praseodymium-doped La2(WO4)3

We present characterization of the hyperfine and quadrupole interactions of praseodymium in La 2 (WO 4 ) 3 . The hyperfine structure of the 3 H 4 (0) → 1 D 2 (0) transition is calculated from a crystal-field analysis and is compared to experimental values retrieved from previous holeburning experiments. The crystal-field wavefunctions are obtained by fitting 42 experimental energy levels, with a good rms standard deviation of 18.3 cm ―1 . It is noteworthy that the energy-level scheme of Pr:La 2 (WO 4 ) 3 is reported for the first time. The experimental branching ratios between individual 3 H 4 (0) → 1 D 2 (0) hyperfine transitions are also fitted. Two different approaches are undertaken, one with a complete diagonalization of a Hamiltonian including the crystal-field, the hyperfine and the quadrupole interactions, another using a spin-Hamiltonian approach based on a second-order perturbation treatment.